Participants will come to the Department of Psychiatry for baseline assessment, including undergoing a structured psychiatric examination and completing baseline self-report measures. If they are interested and eligible they will be asked to complete a series of assessments that will last three days. On day one, they will then be asked to report to the Stanford General Research Center on their next available Wednesday, at 9:00. At that time a medical exam will be performed, bloods were will be drawn and the FMVD (see below) undertaken. They will then be asked to wear a the "lifeshirt," a undergarment worn over the chest that will measure heart rate during the day, and to report their mood and activity on up to 5 occassions using a portable computer attached to the lifeshirt. Each participant will be scheduled to obtain saliva samples using cotton swabs in "salivette devices" at the time of waking, 30 minutes later, and then at 1200h, 1700h, and 2100h on each of two days. Participants were asked to refrigerate each sample immediately after collection, not to eat, drink, smoke, brush their teeth, or use mouthwash in the 30 minutes before collection, and not to drink alcohol during the 8-10 hours prior to collecting samples or during the days of collection. On day two they will return the life-shirt and continue to obtain salivary cortisols. On day three they will be asked to return to the Stanford GCRC to undertaken a psychological stress test. The psychological stress test is a standardized social and cognitive stressor composed of 5 minutes of anticipatory stress, and then 5 minutes of public speaking (simulated job interview) and 5 minutes of mental arithmetic, both done before a panel of 2 evaluators. Subjects were sitting in a comfortable chair throughout the entire procedure. Subjects were informed that their speech would be evaluated by a panel of two expert behavioral coders and that it would be rated on the basis of poise, speaking ability, and expressiveness. During the psychological stress a number of physiologic functions will be measured using sensors attached to the chest and arms. Subjects will also be asked to provide saliva samples between the measurements and to report their mood. At the end of the stress testing they will meet with an investigator to be debriefed.